I own a 04 zx6r and just recently got new sprockets. I went 1 down in front and 2 up in the back. I was told this will affect my speedo and it has. My question is, does anyone know a way i can figure out how fast im really going?. what i mean is like when my speedo says im going 60mph i know for a fact im not going that fast. Is there any kind of online calculator or does anyone know the math where i could just figure it out?. i am aware of a speedohealer but it would just be cheaper to have a mental note of how fast i was going then to buy that thing.